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<p class='vspace'></p><h2>shiftOut()</h2>
<h4>Description</h4>
<p>Shifts out a byte of data one bit at a time.  Starts from either the most (i.e. the leftmost) or least (rightmost) significant bit.  Each bit is written in turn to a data pin, after which a clock pin is pulsed (taken high, then low) to indicate that the bit is available.
</p>
<p class='vspace'></p><p>Note: if you're interfacing with a device that's clocked by rising edges, you'll need to make sure that the clock pin is low before the call to shiftOut(), e.g. with a call to digitalWrite(clockPin, LOW).
</p>
<p class='vspace'></p><p>This is a software implementation; see also the <a class='wikilink' href='Library_SPI.html'>SPI library</a>, which provides a hardware implementation that is faster but works only on specific pins.  
</p>
<p class='vspace'></p><h4>Syntax</h4>
<p>shiftOut(dataPin, clockPin, bitOrder, value)
</p>
<p class='vspace'></p><h4>Parameters</h4>
<p>dataPin: the pin on which to output each bit (<em>int</em>)
</p>
<p class='vspace'></p><p>clockPin: the pin to toggle once the <strong>dataPin</strong> has been set to the correct value (<em>int</em>)
</p>
<p class='vspace'></p><p>bitOrder: which order to shift out the bits; either <strong>MSBFIRST</strong> or <strong>LSBFIRST</strong>.<br />(Most Significant Bit First, or, Least Significant Bit First) 
</p>
<p class='vspace'></p><p>value: the data to shift out. (<em>byte</em>)
</p>
<p class='vspace'></p><h4>Returns</h4>
<p>None
</p>
<p class='vspace'></p><h4>Note</h4>
<p>The <strong>dataPin</strong> and <strong>clockPin</strong> must already be configured as outputs by a call to <a class='wikilink' href='PinMode.html'>pinMode</a>().
</p>
<p class='vspace'></p><p><strong>shiftOut</strong> is currently written to output 1 byte (8 bits) so it requires a two step operation to output values larger than 255.

<pre>
// Do this for MSBFIRST serial
int data = 500;
// shift out highbyte
shiftOut&#40;dataPin, clock, MSBFIRST, &#40;data &gt;&gt; 8&#41;&#41;; &nbsp;
// shift out lowbyte
shiftOut&#40;data, clock, MSBFIRST, data&#41;;

// Or do this for LSBFIRST serial
data = 500;
// shift out lowbyte
shiftOut&#40;dataPin, clock, LSBFIRST, data&#41;; &nbsp;
// shift out highbyte 
shiftOut&#40;dataPin, clock, LSBFIRST, &#40;data &gt;&gt; 8&#41;&#41;;
</pre>

</p>
<p class='vspace'></p><h4>Example</h4>
<p>Tutorial for <a class='wikilink' href='Tutorial_ShiftOut.html'>using a shift register</a>.
</p>

<p class='vspace'></p><h4>See also</h4>
<ul><li><a class='wikilink' href='ShiftIn.html'>shiftIn()</a>
</li><li><a class='wikilink' href='Library_SPI.html'>SPI</a>
</li></ul><p class='vspace'></p><p><a class='wikilink' href='index.html'>Reference Home</a>
</p>
<p class='vspace'></p><p><em>Corrections, suggestions, and new documentation should be posted to the <a class='urllink' href='http://forum.43oh.com/forum/28-energia/' rel='nofollow'>Forum</a>.</em>
</p>
<p class='vspace'></p><p>The text of the Energia Reference is licensed under a
<a class='urllink' href='http://creativecommons.org/licenses/by-sa/3.0/' rel='nofollow'>Creative Commons Attribution-ShareAlike 3.0 License</a>.  Energia reference is based on Arduino reference.  Code samples in the reference are released into the public domain.
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